On 07/09/2013 06:07 AM, Hui Zhang wrote:

Considering that you have 48,8 milliard years in half-time, you are
pretty safe. The problem is rather that it reacts to water and becomes a
strong base, so you want to keep it dry and well protected. Keeping it
in a clock chassi is good enough.

Cheers,
Magnus

On Tue, 09 Jul 2013 11:24:27 +0200
Magnus Danielson magnus@rubidium.dyndns.org wrote:

IIRC Rb is hygroscopic, ie keeping dry wont help, it will react with
the air humidity as well. But then, you have only a couple mg of Rb
in the cell. And the whole thing is enclosed. So you wont get much
exposure anyways. As for toxidity, AFAIK Rb by itself is not toxic.
Rb solution is, as Magnus said, a strong base, but you will get very little
of it and and i am not aware of any toxidity beside being a stron base.
So don't let it get into your eyes and you will be fine :-)

For comparison: Natrium hydroxide is sold in tablet form as un-clogging agent.
It is, for it being a strong base, rated with a high toxidity/danger class,
(about the same as hydrochloric acid) but is not toxic in it self.
Handling it is safe, unless you throw a lot of it into water.
In dry form, the most danger it poses is making soap out of the fat
in your skin :-)

		Attila Kinali

--
The trouble with you, Shev, is you don't say anything until you've saved
up a whole truckload of damned heavy brick arguments and then you dump
them all out and never look at the bleeding body mangled beneath the heap
-- Tirin, The Dispossessed, U. Le Guin

In those tough times, since the General Electric reactors melted down at
Fukushima, and still spewing lots of radiation after more than two
years, a radioactive particle detector is a must have - at least for
gamma radiation.
As for beta particles, you can try visual detection. If you don't see
the blue glow in dielectrics (aka Cherenkov radiation) there's still
some hope...

On 7/9/2013 7:07 AM, Hui Zhang wrote:

Hi,

Toxicity is not the problem. Radioactivity was my biggest concern, when
I ordered my first Rb-clock.The manufacturer told me, there's no
radioactivity, that you have to fear. When the package came I used a
Geiger tube to calm myself down - there was no measurable activity at all.

If the clock doesn't work anymore, be careful when opening it, the bulb
could be broken (though impropable). I don't know how the Rubidium will
react in such a case, but it can react with the air and start to burn
(but remember, it's a very small amount) and you could get some mg of a
strong base, which is corrosive/caustic.

To come to the point: You won't be able to "wreak havoc" with a Rb-lamp...

Volker

Am 09.07.2013 11:40, schrieb Attila Kinali:

Hi
Why are so many people radiophobic? As in ionising radiation. There are far more hazardous things in our hobby, electrocution and falling from a height be two of the big killers. I defy anyone to come up with a confirmed case of death caused by radiation as part of our hobby. Lead, solder flux, mercury, PCB's (the chemical in some caps and transformers) and cleaning solvents are all more harmful to our health. The use of radioisotopes directly or indirectly saves lives every day. Coal fired powerstations release more long life radioactive isotopes ro the environment than a nuclear one would ever be permitted to, plus a load of heavy metals. 
 
Rant off,
Robert G8RPI.

From: Volker Esper ailer2@t-online.de
To: Discussion of precise time and frequency measurement time-nuts@febo.com
Sent: Tuesday, 9 July 2013, 11:33
Subject: Re: [time-nuts] How dangerous if Rb lamp broken?

Hi,

Toxicity is not the problem. Radioactivity was my biggest concern, when
I ordered my first Rb-clock.The manufacturer told me, there's no
radioactivity, that you have to fear. When the package came I used a
Geiger tube to calm myself down - there was no measurable activity at all.

If the clock doesn't work anymore, be careful when opening it, the bulb
could be broken (though impropable). I don't know how the Rubidium will
react in such a case, but it can react with the air and start to burn
(but remember, it's a very small amount) and you could get some mg of a
strong base, which is corrosive/caustic.

To come to the point: You won't be able to "wreak havoc" with a Rb-lamp...

Volker

Am 09.07.2013 11:40, schrieb Attila Kinali:

time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.

Yes but we like coal because if we ignore the dangers and pollution it's co
cheeeeeeap!

I used to play with the old CRT color TVs and would boost the HV up enough to be
able to fog film with the X-rays (not well enough to make images though).  I do
agree with what you say though.

On 7/9/2013 7:49 AM, Robert Atkinson wrote:

Le 9 juil. 2013 à 13:49, Robert Atkinson a écrit :

How true. I can't understand it either.

On Tue, 09 Jul 2013 12:33:11 +0200
Volker Esper ailer2@t-online.de wrote:

If radioactivity is a concern, you should stop eating bananas and
do not go down to your cellar. And for gods sake, stop flying! ;-)

The amount of Rb in a vapor cell is very little. You take in more radiocative
material by eating a banana.

For the Rb to cause serious damage by burning, you need to drop a couple
of gramms into water. Anything else will not cause a fast enough reaction.
Beside, you have only a couple of milligram, not enough to cause anythingm
major.  Also, if the cell is broken it is most likely that the Rb is already
highly oxidized by the time you open it (and thus mostly harmless, beside
it's basic behaviour).

Yes. Broken glass is sharp and will cause serious cuts if not handled
carefully.

		Attila Kinali

--
The trouble with you, Shev, is you don't say anything until you've saved
up a whole truckload of damned heavy brick arguments and then you dump
them all out and never look at the bleeding body mangled beneath the heap
-- Tirin, The Dispossessed, U. Le Guin

Many people are just phobic about radiation, partially becayse tgey don't
understand it.

Some years ago, the DoD was trying to get approval for a Phased Array
early warning RADAR on Cape Cod, MA, called Pave Paws. Public hearings
were held and the public kept asking 'Will the radiation contaminate the
ocean? and 'How long will the radiation contaminate the environment?'

Also, as a freshman a long time ago, I was a subject to measure body fat.
The technique was to go into a shielded chamber (16" thick battleship
aqrmor plate, from the pre-atomic age) and lie under a scintillator
crystal, coupled to an MCA. The number of (K or Ca ?) decays per hour was
measured and the lean body mass calculated.

If you image in the thermal IR, you are seeing images formed by body
emissions.

Radiation is a fact of life. It is used as a boogieman by some, to suit
their agendas.

-John

=============

Am 09.07.2013 14:16, schrieb Attila Kinali:

...yes, and don't use mobiles and so on.

Radioactivity is a concern, because I don't have any serious experience
with it. And I guess, many of us don't. And I totally lack a sense of
the amounts of radioactive radiation. I know well, what a Volt is or an
Amp and I know, where I have to put my fingers and where not on my lab
desk. Going down to my cellar may expose myself to some radiation, but I
don't work there for hours. Sitting at my lab bench for hours, daily, is
another thing, if there is a radioactive contamination of an unknown
radiation dose. Now, that we know, the amount is very little or zero,
we're all happy. That's all, not more, not less. I only wanted to be
cautious, and I guess, Hui, too.

Interesting.

I think so. I only wanted to be careful with my advice, since I'm not a
physicist or a chemist. By the way: I don't eat bananas, but for some
other reason...

Volker

On 07/09/2013 11:40 AM, Attila Kinali wrote:

Thanks for the added wording, I was writing in a hurry. I know it is
hygroscopic, but it at least make the process slower than if you poor
water on it which is more spectacular.

There are Rubidium and Caesium salts that can be consumed safely, and
there is naturally those selling it for it's magic properties.

Indeed. It's a good comparison.

Handle with care.

If you are going to poor water on it, use A LOT.

Cheers,
Magnus

Hi Robert,

On 07/09/2013 01:49 PM, Robert Atkinson wrote:

They know it can be dangerous, but they don't understand the danger, and
becomes overcautious. Kinda good in a way, and tells you more how the
human basic survival instinct works.

There is several things you need to learn and the safety precaustions
takes a bit of knowledge about what material it is, what decay they have
etc. That's a bit more complex than "stay the hell away". Not everyone
has the interest needed to learn how it actually works.

Cheers,
Magnus

Am 09.07.2013 13:49, schrieb Robert Atkinson:

In my opinion, the answere isn't hard to find. Those people don't have
any experience with it and don't know, which information is correct.
Radiation can be dangerous, there's no doubt about it, is it? The
question is: is this paticular situation dangerous. So there's no sense
in mocking someone or making fun of him. We just need enough information
to estimate the risk. It would be better to inform someone who's scared
with precise information.

Since I'm no native speaker, I'm not sure, what exactly you are meaning

• declamatory, elevated, fray, excited?

Thanks

Volker

Rb is not even mentioned in the "The National Institute for Occupational
Safety and Health (NIOSH)" tables as a hazardous substance. Even if
shipped, Rb is listed as a simple Alkali metal.

Volker Esper

--
"Neither the voice of authority nor the weight of reason and argument
are as significant as experiment, for thence comes quiet to the mind."
De Erroribus Medicorum, R. Bacon, 13th century.
"If you don't know what it is, don't poke it."
Ghost in the Shell

Dr. Don Latham AJ7LL
Six Mile Systems LLP
17850 Six Mile Road
POB 134
Huson, MT, 59846
VOX 406-626-4304
Skype: buffler2
www.lightningforensics.com
www.sixmilesystems.com

I do agree with you, generally, on the topic of ionizing radiation and want
to thank you for reminding me to check the batteries in my geiger counter!
I do live with a nuclear power plant upwind from me and thus feel that
maintenance of the instrument is desirable.  And I do remember back in the
"prehysteria" days when, in the middle of a mineralogy lecture, a second
professor broke into the room with long tongs and removed a rock sample that
had been used for identification and was known to be radioactive and quickly
retreated with it.  Until that moment any danger had not been considered.
Not that the lesson did any good because I know that I have a rather large
radioactive sample in our bedroom closet where it has peacefully resided for
some twenty plus years.  I would suggest that anyone who is actively
looking for something to get excited about look into the packaging materials
we use for our foods today!

Sincerest best regards,

Lee A. Mushel,  K9WRU
----- Original Message -----
From: "Robert Atkinson" robert8rpi@yahoo.co.uk
To: "Discussion of precise time and frequency measurement"
time-nuts@febo.com
Sent: Tuesday, July 09, 2013 5:49 AM
Subject: Re: [time-nuts] How dangerous if Rb lamp broken?

An Alkali metal may be simple, but they are surely hazardous. Rb can be
extremely hazardous, as are the other Alkali metals, i.e. Lithium,
Sodium, Potassium and Cesium (and Francium, but that is one of the
rarest elements, due to its highly unstable nature, with its most stable
isotope having a half life of 22 minutes). They can react violently with
water, releasing hydrogen gas that may explode depending on the
conditions. Some of them will ignite with exposure to air.  Note that
the small amount of Rb in a Rb lamp probably mitigates most of danger.

John

On 7/9/2013 3:02 PM, Don Latham wrote:

Hello Robert:

I am a little confuse how exactly much Rb87 in a bulb? Some people say that it's couple millgram,  but you tell me it's half a millgram, which is ture?

You message is good new to me, it let me relax, but I don’t understand Bq/gram unit, would you please convert it to mSV unit, I can know the how many mSV of human is safety by search by internet. I mean in extreme situration, if all Rb87 of buld sprinkled in my table, how many exposure value will I accepet in 24 Hour?

I found some people (other electronics fan) wrote a formula about Rb87 radioactivity calculation, that is:

1mg Rubidium * 27.835 * 0.27835 * 6.02 10^23 / 87/4.88/10^10/2/365/24/36001=625.

So, decay energy=0.283MeV, about 600 electron per second, Is this calculation correct?

27.835=Percent of Rb87

6.02*10^23 = Avogadro's constant

87= Atomic weight

4.88*10^10== Half time of Rb87 (Year)

2 = Rb87 decay to half

365 = day of year

24 = hour of day

3600 = second of hour

I am very glad to read many relay of my email, I want say thanks for everyone. As you said why people be afraid of Rb87 but not other things, I think maybe because we don’t understand it. Such as, I don’t afraid of RF exposure, because I know it, I am a HAM and learned many RF exposure knowledge, but of atom and radioactivity, I have only poor knowledge.

Thanks everyone again, this is amazing mail-list. Say sorry for my poor English.

Hui

At 2013-07-09 19:40:50,"Robert Atkinson" robert8rpi@yahoo.co.uk wrote: